Apparatus, system and method for performing an electrosurgical procedure

ABSTRACT

An apparatus for performing a microwave ablation procedure is provided. The apparatus includes a catheter including an open proximal end and a closed distal end configured to percutaneously access tissue. A directional microwave antenna probe adapted to connect to a source of microwave energy selectively couples to the catheter. The directional microwave antenna is rotatable within the catheter for directing the emission of microwave energy therefrom to tissue

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation application of U.S. application Ser.No. 14/842,199 filed on Sep. 1, 2015, which is a divisional applicationof U.S. application Ser. No. 12/944,951 filed on Nov. 12, 2010, now U.S.Pat. No. 9,119,647, the entire contents of each of which areincorporated herein by reference.

BACKGROUND

Technical Field

The present disclosure relates to an apparatus, system and method forperforming an electrosurgical procedure. More particularly, the presentdisclosure relates to an apparatus, system and method including adirectional microwave antenna probe and a catheter that are configuredto perform a microwave ablation procedure.

Description of Related Art

Microwave ablation procedures, e.g., such as those performed formenorrhagia, are typically done to ablate the targeted tissue todenature or kill the tissue. Many procedures and types of devicesutilizing electromagnetic radiation therapy are known in the art. Suchmicrowave therapy is typically used in the treatment of tissue andorgans such as the prostate, heart, and liver. One non-invasiveprocedure generally involves the treatment of tissue (e.g., a tumor)underlying the skin via the use of microwave energy. Typically,microwave energy is generated by a power source, e.g., microwavegenerator, and transmitted to tissue via a microwave antenna that is fedwith a coaxial cable that operably couples to a radiating section of themicrowave antenna.

To treat the tissue, the radiating section of the microwave antenna maybe positioned inside the tissue of interest, e.g., the tumor, andmicrowave energy may be radiated thereabout. Typically, the microwaveenergy radiates with no specific directionality pattern, i.e., thedirection of the microwave energy is not controlled. For example, undercertain surgical environments, the microwave energy may radiate radiallyoutward in a generally spherical pattern. While this spherical patternof microwave energy may be suitable for treating certain shapes and/ortypes of tissue specimens, e.g., tissue specimens that exhibit agenerally spherical shape, under certain circumstances, this sphericalpattern of microwave energy may not be suitable for treating othershapes and/or types of tissue specimens, such as, for example, in theinstance where the tumor is elongated or otherwise shaped.

SUMMARY

The present disclosure provides a system for performing a microwaveablation procedure. The system includes a catheter including an openproximal end and a closed distal end configured to percutaneously accesstissue. A directional microwave antenna probe adapted to connect to asource of microwave energy selectively couples to the catheter. Thedirectional microwave antenna is rotatable within the catheter fordirecting the emission of microwave energy therefrom to tissue.

The present disclosure provides an apparatus for performing a microwaveablation procedure. The apparatus includes a catheter including an openproximal end and a closed distal end configured to percutaneously accesstissue. A directional microwave antenna probe adapted to connect to asource of microwave energy selectively couples to the catheter. Thedirectional microwave antenna is rotatable within the catheter fordirecting the emission of microwave energy therefrom to tissue.

The present disclosure also provides method of performing a microwaveprocedure. The method includes percutaneously accessing tissue with acatheter including an open proximal end and a closed distal endconfigured to percutaneously access tissue for adjacent placementthereto. A step of the method includes positioning a directionalmicrowave antenna probe adapted to connect to a source of microwaveenergy into the catheter. The directional microwave antenna is rotatablewithin the catheter for directing the emission of microwave energytherefrom to tissue. And, transmitting microwave energy to the microwaveantenna such that a desired tissue effect may be achieved is anotherstep of the method.

BRIEF DESCRIPTION OF THE DRAWING

Various embodiments of the present disclosure are described hereinbelowwith references to the drawings, wherein:

FIG. 1A is a side, perspective view of a system including a directionalprobe and an introducer catheter according to an embodiment of thepresent disclosure;

FIG. 1B is a side, perspective view of the system depicted in FIG. 1Awith the directional probe coupled to the introducer catheter;

FIG. 2 is a perspective view of the introducer catheter depicted inFIGS. 1A and 1B;

FIG. 3 is a side cut-away view of the introducer catheter depicted inFIG. 2;

FIG. 4A is a perspective view of a distal end of the directional probedepicted in FIGS. 1A and 1B;

FIG. 4B is a schematic view of the directional probe as depicted in thearea of detail of FIG. 4A taken along line segment “4B-4B” illustratingan angle of an opening of the directional probe;

FIG. 4B ₋₁ is a schematic view illustrating another angle of the openingof the directional probe;

FIG. 5 is a side, cut-away view of the directional probe depicted inFIG. 4A;

FIG. 6 is a side, cut-away view of a distal end of the directional probecoupled to the introducer catheter depicted in FIG. 1B illustratingfluid flow through the directional probe and the introducer catheter;and

FIGS. 7A and 7B illustrate the directional probe radiating in variousdirections.

DETAILED DESCRIPTION

Detailed embodiments of the present disclosure are disclosed herein;however, the disclosed embodiments are merely examples of thedisclosure, which may be embodied in various forms. Therefore, specificstructural and functional details disclosed herein are not to beinterpreted as limiting, but merely as a basis for the claims and as arepresentative basis for teaching one skilled in the art to variouslyemploy the present disclosure in virtually any appropriately detailedstructure.

In the drawings and in the descriptions that follow, the term“proximal,” as is traditional, will refer to an end that is closer tothe user, while the term “distal” will refer to an end that is fartherfrom the user.

With reference to FIGS. 1A and 1B, a system for performing anelectrosurgical procedure is designated 2. System 2 includes adirectional microwave probe 4 and a catheter 6. Probe 4 is adapted toconnect to one or more suitable electrosurgical energy sources, e.g., amicrowave generator 8. In certain embodiments the probe 4 and catheter 6are both adapted to couple to one or more fluid sources 10 that areconfigured to supply fluid to one or both of the probe 4 and catheter 6.In certain embodiments, the probe 4 and catheter 6 are both adapted tocouple to one or more imaging guidance systems 7 that are configured tofacilitate positioning the catheter 6 and/or probe 4 disposed thereinadjacent tissue.

Continuing with reference to FIGS. 1A and 1B, and with reference toFIGS. 2-3, catheter 6 is illustrated. Catheter 6 is configured topercutaneously access tissue for adjacent placement thereto and toreceive the probe 4 therein. With this purpose in mind, catheter 6includes a proximal end 12, an elongated body portion or shaft 14 and adistal end 16. In the illustrated embodiment, the catheter includes aninlet/outlet port 17 of suitable dimensions that is operably disposedadjacent the proximal end 12. The inlet/outlet port 17 is in fluidcommunication with the fluid source 10 (via a supply hose not shown) anda lumen 24 (FIG. 3) of the catheter 6, to be described in greater detailbelow.

The proximal end 12 is configured to receive the probe 4 therethrough.More particularly, the proximal end 12 is configured to provide asubstantially fluid-tight seal between the catheter 6 and the probe 4when the catheter 6 and the probe 4 are coupled to one another (see FIG.1B). To this end, a diaphragm 18 of suitable configuration is operablydisposed at the proximal end 12 of the catheter 6 (FIGS. 1A-3).

Diaphragm 18 may be made from any suitable material including, but notlimited to rubber, plastic, metal, metal alloy, etc. In the illustratedembodiment, the diaphragm 18 is made from rubber. A rubber diaphragm 18facilitates providing the substantially fluid-tight seal between thecatheter 6 and the probe 4 when the catheter 6 and the probe 4 arecoupled to one another.

Diaphragm 18 includes a generally annular or circumferentialconfiguration with an opening 20 of suitable configuration (FIG. 3)defined therein. Opening 20 is configured to facilitate receiving theprobe 4 therethrough and providing the substantially fluid-tight sealbetween the catheter 6 and the probe 4. To this end, the opening 20includes a diameter that is slightly smaller than a diameter of theprobe 4. The opening 20 flexes or expands to accommodate the slightlylarger diameter of the probe 4. That is, the opening 20 “gives” becauseof the elasticity attributed to the rubber diaphragm 18. In certainembodiments, it may prove useful to coat the diaphragm 18 (or in someinstances the probe 4) with one or more types of lubricious materials,e.g., surgical jelly, PTFE, etc., to decrease the kinetic coefficient offriction between an interior wall of the opening 20 and an exteriorsurface of the probe 4. The opening 20 extends into the lumen 24 of theshaft 14.

Shaft 14 is suitably proportioned and operably coupled to the diaphragm18. Shaft 14 includes a generally elongated configuration and may bemade from any suitable material. More particularly, shaft 14 isconfigured such that when the probe 4 is coupled to the catheter 6, theprobe 4 is capable of transmitting and/or emitting microwave energythrough the shaft 14. With this purpose in mind, shaft 14 is made from aradiofrequency transparent material such as, for example, fiberglass andhigh temperature composite plastic e.g., polyimide, polyether, ketone,etc.

In certain instances, the shaft 12 and/or catheter 6 are configured toselectively receive a substantially rigid introducer sheath 15 ofsuitable proportion that is configured to add structural support to thecatheter 6 and enhance visibility thereof during image-aided placementof the catheter 6 (FIG. 3). In this instance, the sheath 15 may beinserted into the catheter 6 prior to accessing tissue. When thecatheter 6 is positioned adjacent tissue, the sheath 15 may be removedfrom the catheter 6 and the probe 4 may, subsequently, be inserted intothe catheter 6.

In certain instances, the exterior surface of the shaft 14 may includemarkings that are configured to facilitate placement of the catheter 6adjacent a tissue specimen. For example, and in certain instances, itmay prove useful to provide the exterior surface of the shaft 14 withdepth markings 13 (shown in phantom in FIG. 2) for indicating the depthof the inserted catheter in tissue. As noted above, the exterior of theshaft 14 may be coated with one or more lubricious materials for thereasons provided above.

Shaft 14 includes the lumen 24 that is configured such that the probe 4is movable therein. More particularly, the lumen 24 is configured suchthat the probe 4 is translatable and rotatable therein; the significanceof which to be described in greater detail below. That is, the probe 4can move distally and proximally within the lumen 24, while maintaininga free rotational orientation thereabout. To this end, the lumen 24includes diameter that is slightly larger than the diameter of theopening 20 (as best seen in FIG. 3) and a diameter of the probe 4 (asbest seen in FIGS. 7A and 7B). Lumen 24 is in fluid communication withthe inlet/outlet port 17 for providing a fluid, e.g., chilled saline,therein. The lumen 24 is configured to circulate the fluid from theinlet/outlet port 17 and into the probe 4 (see FIG. 1B in combinationwith FIG. 6). For illustrative purposes, the fluid flow is illustratedby directional arrows disposed within the lumen 24 and the probe 4. Incertain instances, the lumen 24 is configured to circulate the fluidfrom the probe 4 and into the inlet/outlet port 17. Lumen 24 extendssubstantially along the length of the shaft 12 and culminates in agenerally arcuate contour adjacent the distal end 16 of the catheter 6,see FIGS. 6-7B.

Distal end 16 is configured to pierce tissue such that the catheter 6may be positioned adjacent (or in some instances into) a tissuespecimen, e.g., a tumor. To this end, distal end 16 includes a generallypointed tip 26. Pointed tip 26 may include any shape that is suitablefor the purposes intended herein. For illustrative purposes, the pointedtip 26 includes a generally conical shape. Pointed tip 26 may be madefrom any suitable material. In the illustrated embodiment, pointed tip26 is made from a material such as metal, ceramic and plastic.

With reference again to FIGS. 1A and 1B, and with reference to FIGS. 4Aand 5, probe 4 is illustrated. Probe 4 is configured to transmit and/oremit electrosurgical energy, e.g., microwave energy, to target tissue,e.g., a tumor, such that a desired tissue effect may be achieved, e.g.,the tumor may be ablated. To this end, probe 4 includes a hub or handle28 (FIG. 1A), a shaft 30 (FIGS. 1A and 4A) that is configured to supportor house an internal coaxial feed or cable 32 (FIGS. 4A and 5), and aconductive distal end or tip 34 (FIGS. 1A, 1B, 4A and 5). In theillustrated embodiment, the probe 4 includes an inlet/outlet port 37 ofsuitable dimensions that is operably disposed on the handle 28 (FIGS. 1Aand 1B). The inlet/outlet port 37 is in fluid communication with thefluid source 10 (via a return hose not shown) and a lumen 38 defined bya shaft 30 (FIGS. 5 and 6), to be described in greater detail below.

With continued reference to FIGS. 1A and 1B, handle 28 is suitablyshaped. More particularly, handle 28 may be ergonomically designed toprovide a user with an ease of use with respect to rotational and distaland/or proximal positioning within the catheter 6. With this purpose inmind, handle 28 includes a generally circumferential configuration thatis configured to support the inlet/outlet port 37 and a connector 42that couples to a power cable 44 that selectively couples to themicrowave generator 8.

Power cable 44 may be any suitable power cable that is capable ofconducting electrosurgical energy. Connector 42 provides electrosurgicalenergy to the conductive distal end 34 via the internal coaxial feed 32that extends from the proximal end 46 of the probe 4 and includes aninner conductor tip 48 that is operatively disposed adjacent the distalend 34 (as best seen in FIG. 5). As is common in the art, internalcoaxial feed 32 includes a dielectric material 43 and an outer conductor45 surrounding each of the inner conductor tip 48 and dielectricmaterial.

Shaft 30 is operably coupled to the handle 28 and is configured to houseor support the internal coaxial feed 32 therein. In the illustratedembodiment, coaxial feed 32 is operably coupled to an internal frame ofthe shaft 30 by any suitable coupling methods.

Shaft 30 includes a generally elongated configuration with the internalcavity or lumen 38 extending along a length thereof. In the illustratedembodiment, shaft 30 is in fluid communication with the inlet/outletport 37 via the lumen 38. The lumen 38 channels the fluid, e.g., chilledsaline, from the catheter 6 to the inlet/outlet port 37 and ultimatelyback to the fluid source 10.

Shaft 30 may be made from any suitable material including, but notlimited to plastic, metal, metal alloy, etc. In the illustratedembodiment, shaft 30 is made from a lightweight metal, such as, forexample, aluminum.

Shaft 30 extends from the proximal end 46 of the probe 4 and includes orcouples to the conductive distal end 34 by one or more suitable couplingmethods, e.g., brazing, welding, soldering. In certain embodiments,shaft 30 may be monolithically formed with the conductive distal end 34.

With reference again to FIG. 4A, conductive distal end 34 is configuredfor directing the emission of electrosurgical energy. To this end,conductive distal end 34 includes a generally flared configuration withan aperture or opening 50 of suitable proportion (FIGS. 1A, 4A, and5-7B) disposed adjacent a distal tip 52.

Distal tip 52 includes a generally arcuate configuration that iscontoured to match the contour of the distal end of the lumen 24 of thecatheter 6 (FIGS. 6 and 7A-7B). Matching the contours of the distal tip52 and distal end of the lumen 24 facilitates directing fluid flowthrough the opening 50 when the distal tip 52 has “bottomed out” at orcontacted the distal end of the lumen 24. That is, a substantiallyfluid-tight seal is present at a boundary between the distal tip 52 anddistal end of the lumen 24 when the distal tip 52 has “bottomed out” ator contacted the distal end of the lumen 24 and forces the fluid throughthe opening 50.

Opening 50 extends along a length of the distal end 34 and includes agenerally elongated configuration configured to maximize and/orconcentrate electrosurgical energy transmission therefrom. To facilitatedirecting the electrosurgical energy from conductive distal tip 34 totissue, the opening 50 is angled (see FIG. 4A in combination with FIGS.4B and 4B ₋₁). The angle of the opening 50 ranges from about 45° (FIG.4B ₋₁) to about 250° (FIG. 4B).

Operation of system 2 is described in terms of use of a method forperforming an electrosurgical procedure, e.g., a microwave ablationprocedure. Catheter 6 with introducer sheath 15 disposed therein is usedto percutaneously access underlying tissue (FIG. 6). In certaininstances, the imaging guidance system 7 may be utilized to navigate thecatheter 6 adjacent a tissue specimen of interest, e.g., a tumor. Oncethe catheter 6 is in position, the introducer sheath 15 is removed andthe probe 4 is introduced into the lumen 24 of the catheter 6 via theopening 20 (FIGS. 1B and 6). A substantially fluid-tight seal is presentbetween the opening 20 and the exterior surface of the shaft 30 of theprobe 4 when the probe 4 is introduced into the catheter 6.

Thereafter, microwave generator 8 is activated and microwave energy istransmitted to the inner conductor tip 48 and emitted from theconductive distal tip 34 via the opening 50 (FIG. 7A). The opening 50and the angle thereof facilitate directing the radiating microwaveenergy from the opening 50 to specific locations along the targettissue. Under certain surgical environments or conditions, it may provenecessary to treat different locations along the target tissue, in thisinstance, a user may translate and/or rotate the probe 4 within thelumen 24 of the catheter 6 (FIG. 7B). During the microwave procedure, itmay prove useful to cool the inner conductor 48 and or conductive distaltip 34. In this instance, the fluid supply source 10 may be utilized tocirculate fluid, e.g., chilled saline, to the inlet/outlet port 17 onthe catheter 6 and through the lumen 24 (FIG. 6). The chilled salinereturns through the opening 50 of the probe 4 and through the lumen 38(FIG. 6) to the inlet/outlet port 37 where it is directed back to thefluid supply source via the return hose. As can be appreciated, thecirculatory path of the chilled saline may be reversed. That is, thechilled saline may be supplied to the probe 4 and returned to the fluidsupply source 10 via the catheter 6.

From the foregoing and with reference to the various figure drawings,those skilled in the art will appreciate that certain modifications canalso be made to the present disclosure without departing from the scopeof the same. For example, it in certain embodiments, a perforated,non-conductive dielectric window 54 (FIG. 1A) may be operably positionedabout the opening 52 to allow fluid flow while providing additionalprotection to the coaxial feed 32 including the inner conductor tip 48.More particularly, the non-conductive dielectric window 54 functions toprotect to the coaxial feed 32 including the inner conductor tip 48 fromadjacent tissue structure, bone matter, fluid, or other matter that maypose a possible threat to the coaxial feed 32 including the innerconductor tip 48 during the course of the electrosurgical procedure. Forillustrated purposes, in FIG. 1A the non-conductive dielectric window 54is shown separated from the opening 52. As can be appreciated, thenon-conductive dielectric window 54 may be coupled to the opening 54and/or the distal end 34 via one or more suitable coupling methods,e.g., an adhesive made from an epoxy resin.

While several embodiments of the disclosure have been shown in thedrawings, it is not intended that the disclosure be limited thereto, asit is intended that the disclosure be as broad in scope as the art willallow and that the specification be read likewise. Therefore, the abovedescription should not be construed as limiting, but merely asexemplifications of particular embodiments. Those skilled in the artwill envision other modifications within the scope and spirit of theclaims appended hereto.

What is claimed is:
 1. A system for performing a microwave ablationprocedure, comprising: a source of microwave energy; a catheterincluding an open proximal end and a closed distal end configured topercutaneously access tissue; and a directional microwave antenna probeadapted to connect to the source of microwave energy, the directionalmicrowave antenna selectively coupling to the catheter and rotatabletherein for directing the emission of microwave energy therefrom totissue.
 2. A system according to claim 1, wherein the catheter is madefrom a radiofrequency transparent material.
 3. A system according toclaim 2, wherein the radiofrequency transparent material is selectedfrom the group consisting of fiberglass and high temperature compositeplastic.
 4. A system according to claim 1, wherein the distal end of thecatheter is made from a material selected from the group consisting ofmetal, ceramic and plastic.
 5. A system according to claim 1, wherein asubstantially flexible shaft is operably disposed between the proximalend and distal end of the catheter and includes a lumen that extendssubstantially along a length thereof.
 6. A system according to claim 5,wherein the lumen is in fluid communication with an inlet/outlet portthat is operably disposed adjacent the proximal end of the catheter. 7.A system according to claim 1, wherein a diaphragm is operably disposedat the proximal end of the catheter and is configured to provide asubstantially fluid-tight seal between the catheter and the directionalmicrowave antenna probe when the catheter and the directional microwaveantenna probe are operably coupled to one another.
 8. A system accordingto claim 1, further including an image guidance device.
 9. A systemaccording to claim 8, wherein the imaging guidance device is selectedfrom the group consisting of a CAT scan device, an ultra sound deviceand a magnetic imaging device.
 10. A system according to claim 1,wherein the catheter is configured to selectively receive asubstantially rigid introducer sheath configured to add structuralsupport to the catheter and enhance visibility thereof duringimage-aided placement of the catheter.
 11. A system according to claim1, wherein a proximal end of the directional microwave antenna probeincludes: a handle that is configured to operably couple to the sourceof microwave energy and an inlet/outlet port that is in fluidcommunication with a lumen defined substantially along a lengthdirectional microwave antenna probe; and a distal end of the directionalmicrowave antenna probe is configured for directing the emission ofmicrowave energy.
 12. A system according to claim 11, wherein the distalend of the directional microwave antenna probe is flared and includes anopening defined therein.
 13. A system according to claim 11, wherein thedistal end of the directional microwave antenna includes a perforateddielectric window that is configured to facilitate fluid flow.
 14. Anapparatus for performing a microwave ablation procedure, comprising: acatheter including an open proximal end and a closed distal endconfigured to percutaneously access tissue; and a directional microwaveantenna probe adapted to connect to a source of microwave energy, thedirectional microwave antenna selectively coupling to the catheter androtatable therein for directing the emission of microwave energytherefrom to tissue.
 15. A method of performing an electrosurgicalprocedure, comprising: percutaneously accessing tissue with a catheterincluding an open proximal end and a closed distal end; positioning adirectional microwave antenna probe into the catheter; transmittingmicrowave energy to the directional microwave antenna probe such that adesired tissue effect may be achieved; repositioning the directionalmicrowave antenna probe in the catheter; and transmitting the microwaveenergy to the directional microwave antenna probe.
 16. A methodaccording to claim 15, wherein the catheter is made from aradiofrequency transparent material selected from the group consistingof fiberglass and high temperature composite plastic.
 17. A methodaccording to claim 16, wherein a distal end of the catheter is made froma material selected from the group consisting of metal, ceramic andplastic.
 18. A method according to claim 16, further comprising the stepof providing a fluid to the directional microwave antenna probe via alumen in fluid communication with an inlet/outlet port operably disposedadjacent the proximal end of the catheter.
 19. A method according toclaim 15, further comprising the step of providing a substantiallyfluid-tight seal between the catheter and the directional microwaveantenna probe when the catheter and the directional microwave antennaprobe are operably coupled to one another via a diaphragm operablycoupled at a proximal end of the catheter.